Medical devices such as drug pumps are known. Drug pumps often are grouped into types such as so-called ambulatory pumps, peristaltic pumps, syringe pumps, gravity-feed pumps, elastomeric pumps, multichannel pumps. Such pumps may also provide a so-called PCA (or, “patient-controlled analgesia”) function, depending upon a particular medical need. Although these groupings are often helpful for a general understanding and characterization of drug pumps per se, such terminology is neither limiting nor conclusive and may at times be used interchangeably and variably in the medical arts.
PCA pumps have proven to be particularly useful to both healthcare practitioners and patients. A PCA pump is designed to permit a patient to safely self-medicate with pain medications. By using a PCA pump under an order of a healthcare practitioner, a patient receives a dose of medication by activating a control on, or connection to, the pump such as a push-button activator or switch. Such activation as desired by the patient starts a pumping mechanism in the PCA pump which delivers a measured dose of a fluidic drug (e.g., a liquid narcotic medication) from the cassette to the patient via an intravenous or other fluid line within an allowable time interval. If a PCA command is activated during a time interval in which an allowable dose has already been administered, the pump may be “locked out” and intentionally rendered unable to deliver the dose until the appropriate time interval has passed—thereby safely preventing the patient from taking more than a maximum allowable dose of medication during a measured time interval. The PCA pump may also record a volume of the drug delivered over selected time intervals. The PCA pump may also be queried, to chart the volume of the drug delivered and a number of doses administered to the patient. PCA pumps may also provide any number of other safety features individually or in various combinations—such as, for example, enforcing a maximum number of self-administered doses over a programmable time period and enforcing a maximum amount of drug delivered over a programmable time period.
When a patient is in, e.g., post-operative recovery and no longer requires a PCA drug delivered through a fluid line such as an intravenous set, substantially solid medications (e.g., pills, tablets, capsules containing liquid, granular, or powdered medications, and the like) are often prescribed to be taken orally by the patient in an effort to increase the patient's comfort and reduce risks of infection associated with intravenous drug delivery. In such circumstances, it would be particularly advantageous to provide the functionality and safety features of a PCA drug pump to a patient taking substantially solid medications. Unfortunately, however, there heretofore has been no provision for dispensing substantially solid medication to a patient by way of a PCA pump.
Therefore, it would be particularly useful and advantageous to provide a PCA pump that also is capable of dispensing substantially solid medication to a patient.